0 votes
43 views
in Coordination Chemistry by (138k points)
What is the synthesis procedure of a coordination compound, [Co(NH3)6]Cl3, and how can the product be characterized using various analytical techniques like UV-Vis spectroscopy and infrared spectroscopy?

1 Answer

0 votes
by (138k points)
The synthesis procedure of the coordination compound [Co NH3 6]Cl3 involves the reaction of cobalt III  chloride hexahydrate  CoCl36H2O  with concentrated ammonia  NH3  solution. Here's a step-by-step procedure:1. Dissolve an appropriate amount of CoCl36H2O in a small volume of distilled water to form a dark red solution.2. Slowly add concentrated ammonia solution to the CoCl3 solution while stirring. The solution will initially turn brown and then change to a deep purple color, indicating the formation of [Co NH3 6]Cl3.3. Continue adding ammonia until the solution becomes clear and no further color change is observed.4. Allow the solution to stand undisturbed for a few hours or overnight to allow the [Co NH3 6]Cl3 crystals to form.5. Filter the solution to collect the purple [Co NH3 6]Cl3 crystals.6. Wash the crystals with a small amount of cold distilled water and then with ethanol to remove any remaining impurities.7. Dry the crystals in air or in a vacuum desiccator.Characterization of [Co NH3 6]Cl3 using UV-Vis spectroscopy and infrared spectroscopy:1. UV-Vis spectroscopy: Dissolve a small amount of the synthesized [Co NH3 6]Cl3 in distilled water or another suitable solvent. Measure the UV-Vis spectrum of the solution using a UV-Vis spectrophotometer. The spectrum should show an absorption band in the visible region, corresponding to the d-d transition of Co III  in the octahedral complex. The exact position of the absorption band will depend on the ligand field strength of the ammonia ligands.2. Infrared spectroscopy: Prepare a KBr pellet containing a small amount of the synthesized [Co NH3 6]Cl3 and measure the infrared spectrum using an FTIR spectrometer. The spectrum should show characteristic bands corresponding to the stretching and bending vibrations of the NH3 ligands. The N-H stretching vibrations typically appear in the range of 3300-3500 cm-1, while the N-H bending vibrations are usually observed in the range of 1600-1650 cm-1. The absence of any bands related to water or other impurities in the spectrum will confirm the purity of the synthesized compound.
Welcome to Sarvan Science Q&A, where you can ask questions and receive answers from other members of the community.
...